Also if the yerk/accel is too low, the changes in flow/speed can make gaps while doing too layers if there's no room for the head to achieve a minimum speed. Also it can make weird effects on corners that affect geometry.

Some test photos made on the um3 with various test, fixes, experiments and etc etc. Ofc print without top/bottom and 2-3 perimeters. 0.2 layer height somewhere between 0.1-0.2 should show a good debug I think.

Upss sorry I did delete all my photos of ringing tests... Anyhow, is a good test.

At 500 acceleration + 5 jerk the ringing should disappear completely but on the corners you will see a slight deformation of the change of vector, making the square corners a bit rounder than normal (ofc you can't do a perfect 90 degree change).

The part that this test doesn't cover is the top layer small areas with zigzag. The lower the acceleration/jerk the more troubles the feeder will have to make them perfect, leaving gaps (due delay from pressure going to the extruder from the bowden pressure/relax delay). So when the speed goes down too much (too low jerk) artifacts can appear (more visible on top layer).

Hi antiklesys !
Seeing the photos, it seems you have also a Z problem !?
here it's done with the UM2 , the under print shows the improve by lowering the acceleration and jerk settings
I think with UMO you can get something close to that, Neotko would confirm ?